1. Field of the Invention
This invention relates generally to capacitors, and, more particularly, to integrated circuit capacitors.
2. Description of the Related Art
Capacitors are found in virtually all electronic circuits. Many such circuits require the use of a variable or programmable capacitor, to provide a needed capacitance value in a tunable RF circuit, for example, or to generate a desired waveform.
Circuits of this type are often fabricated as an integrated circuit (IC). When this is the case, the means by which the variable or programmable capacitance is provided are ideally compatible with the processes required to fabricate the IC. There are several known variable IC capacitor types, such as varactors or op amp-boosted Miller capacitances, but these approaches impose limitations on capacitance range and/or maximum capacitance that may be unacceptable.